RODRIGO OLIVA PEREZ

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Assunto: Rectal cancer ×

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  • article 41 Citação(ões) na Scopus
    Consolidation chemotherapy during neoadjuvant chemoradiation (CRT) for distal rectal cancer leads to sustained decrease in tumor metabolism when compared to standard CRT regimen
    (2016) HABR-GAMA, Angelita; PEREZ, Rodrigo O.; JULIAO, Guilherme P. Sao; PROSCURSHIM, Igor; FERNANDEZ, Laura M.; FIGUEIREDO, Marleny N.; GAMA-RODRIGUES, Joaquim; BUCHPIGUEL, Carlos A.
    Background: Neoadjuvant CRT may lead to significant tumor regression in patients with rectal cancer. Different CRT regimens with consolidation chemotherapy may lead to increased rates of complete tumor regression. The purpose of this study was to understand tumor metabolic activity following two different neoadjuvant CRT regimens using sequential PET/CT imaging in two different intervals following RT. Methods: Patients with cT2-4 N0-2 M0 rectal cancer treated by standard CRT (54Gy and 2 cycles of 5FU-based chemotherapy) or extended CRT (54Gy and 6 cycles of 5FU-based chemotherapy) underwent sequential PET/CT imaging at baseline, 6 weeks and 12 weeks from radiation completion. Results: 99 patients undergoing standard CRT were compared to 12 patients undergoing CRT with consolidation chemotherapy. Patients treated with consolidation CRT had increased rates of complete clinical or pathological response (66 % vs. 23 %; p < 0.001). SUVmax variation between baseline and 6 weeks (88 % vs. 63 %; p < 0.001) and between baseline and 12 weeks (90 % vs. 57 %; p < 0.001) were significantly more pronounced among patients undergoing extended CRT with consolidation chemotherapy. An increase in SUVmax between 6 and 12 weeks was observed in 51 % of patients undergoing standard and 18 % of patients undergoing consolidation CRT (p = 0.04). Conclusions: Most of the reduction in tumor metabolism after neoadjuvant CRT occurs within the first 6 weeks from RT completion. In patients undergoing CRT with consolidation chemotherapy, tumors are less likely to regain metabolic activity between 6 and 12 weeks. Therefore, assessment of tumor response may be safely postponed to 12 weeks in patients undergoing extended CRT with consolidation chemotherapy.
  • article 63 Citação(ões) na Scopus
    Baseline T Classification Predicts Early Tumor Regrowth After Nonoperative Management in Distal Rectal Cancer After Extended Neoadjuvant Chemoradiation and Initial Complete Clinical Response
    (2017) HABR-GAMA, Angelita; JULIAO, Guilherme Pagin Sao; GAMA-RODRIGUES, Joaquim; VAILATI, Bruna Borba; ORTEGA, Cinthia; FERNANDEZ, Laura Melina; ARAUJO, Sergio Eduardo Alonso; PEREZ, Rodrigo Oliva
    BACKGROUND: Selected patients with rectal cancer and complete clinical response after neoadjuvant chemoradiation have been managed nonoperatively with acceptable outcomes. However, approximate to 20% of these patients will develop early tumor regrowth. Identification of these patients could select candidates for more intensive follow-up. OBJECTIVE: The purpose of this study was to investigate the influence of baseline radiological T classification on recurrences after a complete clinical response managed nonoperatively after chemoradiation. DESIGN: This was a retrospective review of a prospective collected database. SETTINGS: The study was conducted at a single center. PATIENTS: Patients with distal rectal cancer (cT2-4N0-2M0) undergoing extended chemoradiation (54 Gy + 5-fluorouracil-based chemotherapy) were eligible. Patients were reassessed for tumor response at 10 weeks after radiation completion. Patients with complete clinical response (clinical, radiological, and endoscopic) were managed nonoperatively and strictly followed. MAIN OUTCOMES MEASURES: Complete clinical response rates, early tumor regrowth rates (<12 mo), local recurrence-free survival, and distant metastases-free survival were measured. RESULTS: A total of 91 consecutive patients with rectal cancer underwent extended chemoradiation. Sixty-one patients developed initial complete clinical response (67%). cT2 patients developed similar initial complete clinical response rates compared with cT3/T4 (72% vs 63%; p = 0.403). Early tumor regrowths were more frequent among baseline cT3/4 when compared with cT2 patients (30% vs 3%; p = 0.007). There were no differences in late local recurrences (p = 0.593) or systemic recurrences (p = 0.387). Local recurrence-free survival was significantly better for cT2 patients at 1 year (96% vs 69%; p = 0.009). After Cox regression analysis, baseline T stage was an independent predictor of improved local recurrence-free survival at 1 year (p = 0.03; OR = 0.09 (95% CI, 0.01-0.81)). LIMITATIONS: This study was limited by its small sample size, retrospective nature, and short follow-up. CONCLUSIONS: cT2 patients who develop complete clinical response after extended chemoradiation managed nonoperatively are less likely to develop early tumor regrowths when compared with cT3/4 patients. cT3/4 patients should undergo more intensive follow-up after a complete clinical response to allow for early detection of early regrowths.
  • article 95 Citação(ões) na Scopus
    Achieving a Complete Clinical Response After Neoadjuvant Chemoradiation That Does Not Require Surgical Resection: It May Take Longer Than You Think!
    (2019) HABR-GAMA, Angelita; JULIAO, Guilherme P. Sao; FERNANDEZ, Laura M.; VAILATI, Bruna B.; ANDRADE, Andres; ARAUJO, Sergio E. A.; GAMA-RODRIGUES, Joaquim; PEREZ, Rodrigo O.
    BACKGROUND: Patients with rectal cancer who achieve complete clinical response after neoadjuvant chemoradiation have been managed by organ-preserving strategies and acceptable long-term outcomes. Controversy still exists regarding optimal timing for the assessment of tumor response after neoadjuvant chemoradiation. OBJECTIVE: The purpose of this study was to estimate the time interval for achieving complete clinical response using strict endoscopic and clinical criteria after a single neoadjuvant chemoradiation regimen. DESIGN: This was a retrospective review of consecutive patients managed by 54-Gy and consolidation 5-fluorouracil-based chemotherapy. Assessment of response was performed at 10 weeks after radiation. Patients with suspected complete clinical response were offered watch-and-wait strategy and reassessment every 6 to 8 weeks until achievement of strict criteria of complete clinical response or overt residual cancer. SETTINGS: This study was conducted at a single tertiary care center. PATIENTS: Patients with complete clinical response who underwent a successful watch-and-wait strategy until last follow-up were eligible. Dates of radiation completion and achievement of strict endoscopic and clinical criteria (mucosal whitening, teleangiectasia, and no ulceration or irregularity) were recorded. Patients with incomplete response or with initial complete clinical response followed by local recurrence or regrowth were excluded. MAIN OUTCOMES MEASURES: The distribution of time intervals between completion of radiation and achievement of strict complete clinical response was measured. Patients who achieved early complete clinical response (<= 16 wk) were compared with late complete clinical response (>16 wk). RESULTS: A total of 49 patients achieved complete clinical response and were successfully managed nonoperatively. A median interval of 18.7 weeks was observed for achieving strict complete clinical response. Only 38% of patients achieved complete clinical response between 10 and 16 weeks from radiation completion. Patients with earlier cT status (cT2/T3a) achieved a complete clinical response significantly earlier when compared with those patients with more advanced disease (T3b-d/4; 19 vs 26 wk; p = 0.03). LIMITATIONS: This was a retrospective study with a small sample size. CONCLUSIONS: Assessment at 10 to 16 weeks may detect a minority of patients who achieve complete clinical response without additional recurrence after neoadjuvant chemoradiation. Patients suspected for a complete clinical response should be considered for reassessment beyond 16 weeks before definitive management when considered for a watch and wait strategy. See Video Abstract at http://links.lww.com/DCR/A901.
  • article 378 Citação(ões) na Scopus
    Watch and Wait Approach Following Extended Neoadjuvant Chemoradiation for Distal Rectal Cancer: Are We Getting Closer to Anal Cancer Management?
    (2013) HABR-GAMA, Angelita; SABBAGA, Jorge; GAMA-RODRIGUES, Joaquim; JULIAO, Guilherme P. Sao; PROSCURSHIM, Igor; AGUILAR, Patricia Bailao; NADALIN, Wladimir; PEREZ, Rodrigo O.
    BACKGROUND: No immediate surgery (Watch and Wait) has been considered in select patients with complete clinical response after neoadjuvant chemoradiation to avoid postoperative morbidity and functional disorders after radical surgery. OBJECTIVE: The purpose of this study was to demonstrate the long-term results of patients who had a complete clinical response following an alternative chemoradiation regimen and were managed nonoperatively. DESIGN: This is a prospective study. SETTINGS: This study was conducted at a single center. PATIENTS: Seventy consecutive patients with T2-4N0-2M0 distal rectal cancer were studied. Neoadjuvant chemoradiotherapy included 54 Gy and 5-fluorouracil/leucovorin delivered in 6 cycles every 21 days. Patients were assessed for tumor response at 10 weeks from radiation completion. Patients with incomplete clinical response were referred to immediate surgery. Patients with complete clinical response were not immediately operated on and were monitored. MAIN OUTCOME MEASURES: The primary outcomes measured were the initial complete clinical response rates after 10 weeks and the sustained complete clinical response rates after 12 months from chemoradiotherapy. RESULTS: One patient died during chemoradiotherapy because of cardiac complications. Forty-seven (68%) patients had initial complete clinical response. Of these, 8 developed local regrowth within the first 12 months of follow-up (17%). Thirty-nine sustained complete clinical response at a median follow-up of 56 months (57%). An additional 4 patients (10%) developed late local recurrences (>12 months of follow-up). Overall, 35 patients never underwent surgery (50%). LIMITATIONS: This study is limited by the short follow-up and small sample size. CONCLUSION: Extended chemoradiation therapy with additional chemotherapy cycles and 54 Gy of radiation may result in over 50% of sustained (>12 months) complete clinical response rates that may ultimately avoid radical rectal resection. Local failures occur more frequently during the initial 12 months of follow-up in up to 17% of cases, whereas late recurrences are less common but still possible, leading to 50% of patients who never required surgery. Strict follow-up may allow salvage therapy in the majority of these patients (see Video, Supplemental Digital Content 1, http://links.lww.com/DCR/A113.)
  • article 105 Citação(ões) na Scopus
    Transanal Endoscopic Microsurgery for Residual Rectal Cancer (ypT0-2) Following Neoadjuvant Chemoradiation Therapy: Another Word of Caution
    (2013) PEREZ, Rodrigo Oliva; HABR-GAMA, Angelita; LYNN, Patricio Bernardo; JULIAO, Guilherme Pagin Sao; BIANCHI, Romina; PROSCURSHIM, Igor; GAMA-RODRIGUES, Joaquim
    BACKGROUND: Significant tumor downstaging among patients with rectal cancer following neoadjuvant chemoradiation has raised the issue of offering patients with small residual cancers restricted to the bowel wall an alternative treatment strategy to total mesorectal excision. Transanal endoscopic microsurgery may allow proper primary tumor resection with promising oncological outcomes, less postoperative morbidity, and minimal long-term sexual, urinary, and fecal continence disorders in comparison with radical resection. OBJECTIVE: The aim of this study was to determine the oncological outcomes of patients with residual rectal cancers restricted to the rectal wall (ypT0-2) following neoadjuvant chemoradiation and transanal endoscopic microsurgery. DESIGN: This study considered a prospective cohort of patients with residual rectal cancers following neoadjuvant chemoradiation treated by transanal endoscopic microsurgery and no additional systemic therapy. SETTINGS: This study was a single-institution experience. PATIENTS: Patients with adenocarcinoma of the rectum located no more than 7 cm from the anal verge and endorectal ultrasound-or magnetic resonance-staged cT2-4N0-2M0 treated by neoadjuvant chemoradiation (50.4-54 Gy and 5-fluorouracil-based chemotherapy) were eligible for the study. Patients with small residual tumors (<= 3 cm) radiologically staged ycT0-2N0 were treated by transanal endoscopic microsurgery. INTERVENTIONS: Transanal endoscopic microsurgery was performed. MAIN OUTCOME MEASURES: The primary outcome measured was local recurrence. RESULTS: Of the 27 patients treated by transanal endoscopic microsurgery, 3 had ypT0, 6 had ypT1, and 18 had ypT2 cancers. All patients underwent R0 transanal endoscopic microsurgery excision. Local recurrence was observed in 4 (15%) patients after a median follow-up of 15 months. Only lymphovascular invasion was an independent predictive factor for local failure (p = 0.04). Tumor size, ypT status, T-status downstaging, lateral/radial margins, and tumor regression grade were not predictors of local failure. LIMITATIONS: This study was limited by the small sample size and limited follow-up. CONCLUSIONS: A local failure rate of 15% after transanal endoscopic microsurgery for patients with residual rectal cancers restricted to the bowel wall (ypT0-2) may limit the indication of this procedure to highly selected patients as an alternative to standard radical total mesorectal excision.
  • article 98 Citação(ões) na Scopus
    Impact of Organ-Preserving Strategies on Anorectal Function in Patients with Distal Rectal Cancer Following Neoadjuvant Chemoradiation
    (2016) HABR-GAMA, Angelita; LYNN, Patricio B.; JORGE, J. Marcio N.; JULIAO, Guilherme P. Sao; PROSCURSHIM, Igor; GAMA-RODRIGUES, Joaquim; FERNANDEZ, Laura M.; PEREZ, Rodrigo O.
    BACKGROUND: Organ-preserving strategies have been considered for patients with distal rectal cancer and complete or near-complete response to neoadjuvant chemoradiation to avoid the functional consequences of radical surgery. Transanal endoscopic microsurgery and no immediate surgery (watch and wait) have been considered in selected patients. OBJECTIVE: The aim of this study is to compare anorectal function following these 2 organ-preserving strategies (transanal endoscopic microsurgery and watch and wait) for rectal cancer with complete or near-complete response to neoadjuvant chemoradiation. DESIGN: This study is based on the comparison of prospectively collected data. SETTINGS: This study was conducted at a single center. PATIENTS: Consecutive patients with distal rectal cancer undergoing neoadjuvant chemoradiation (50.4-54 Gy and 5-fluorouracil-based chemotherapy) were prospectively studied. Patients with complete clinical response were managed by watch and wait. Patients with near-complete response (<= 3 cm, ycT1-2N0) were managed by transanal endoscopic microsurgery. MAIN OUTCOME MEASURES: Functional outcomes were determined by anorectal manometry and Fecal Incontinence Index and Quality of Life assessment. RESULTS: Two groups of patients were included in the study. Twenty-nine patients with near-complete response undergoing transanal endoscopic microsurgery and 53 with complete response after watch and wait were assessed. Baseline features were similar between groups. Patients undergoing transanal endoscopic microsurgery had worse resting/squeeze pressures (p = 0.004) and rectal capacity (p = 0.002). In addition, their incontinence scores (2.3 vs 6.5; p < 0.001) and quality-of-life questionnaire responses (in all domains; p <= 0.01) were significantly worse in comparison with patients undergoing watch and wait. LIMITATIONS: This study was limited by the small sample size and the absence of baseline anorectal function information. CONCLUSIONS: Nonoperative management of patients with complete clinical response following chemoradiation results in better anorectal function in comparison with patients with near-complete response managed by transanal endoscopic microsurgery. In the absence of clinically detectable residual cancer, this latter approach may result in significant worsening of anorectal function.
  • article 28 Citação(ões) na Scopus
    Is neoadjuvant chemoradiation with dose-escalation and consolidation chemotherapy sufficient to increase surgery-free and distant metastases-free survival in baseline cT3 rectal cancer?
    (2018) JULIAO, Guilheime Pagin Sao; HABR-GAMA, Angelita; VAILATI, Bruna Borba; AGUILAR, Patricia Bailao; SABBAGA, Jorge; ARAUJO, Sergio Eduardo Alonso; MATTACHEO, Adrian; ALEXANDRE, Flavia Andrea; FERNANDEZ, Laura Melina; GOMES, Diogo Bugano; GAMA-RODRIGUES, Joaquim; PEREZ, Rodrigo Oliva
    Patients with cT3 rectal cancer are less likely to develop complete response to neoadjuvant chemoradiation (nCRT) and still face significant risk for systemic relapse. In this setting, radiation (RT) dose-escalation and consolidation chemotherapy in ""extended"" nCRT regimens have been suggested to improve primary tumor response and decrease the risks of systemic recurrences. For these reasons we compared surgery-free and distant-metastases free survival among cT3 patients undergoing standard or extended nCRT. Methods: Patients with distal and non-metastatic T3 rectal cancer managed by nCRT were retrospectively reviewed.. Patients undergoing standard CRT (50.4 Gy and 2 cycles of 5FU-based chemotherapy) were compared to those undergoing extended CRT (54 Gy and 6 cycles of 5FU-based chemotherapy). Patients were assessed for tumor response at 8-10 weeks. Patients with complete clinical response (cCR) underwent organ-preservation strategy (Watch & Wait). Patients were referred to salvage surgery in the event of local recurrence during follow-up. Cox's logistic regression was performed to identify independent features associated with improved surgery-free survival after cCR and distant-metastases-free survival. Results: 155 patients underwent standard and 66 patients extended CRT. Patients undergoing extended CRT were more likely to harbor larger initial tumor size (p = 0.04), baseline nodal metastases (cN+; p < 0.001) and higher tumor location (p = 0.02). Cox-regression analysis revealed that the type of nCRT regimen was not independently associated with distinct surgery-free survival after cCR or distant-metastases-free survival (p > 0.05). Conclusions: Dose-escalation and consolidation chemotherapy are insufficient to increase long-term surgery-free survival among cT3 rectal cancer patients and provides no advantage in distant metastases-free survival.
  • article 106 Citação(ões) na Scopus
    Role of biopsies in patients with residual rectal cancer following neoadjuvant chemoradiation after downsizing: can they rule out persisting cancer?
    (2012) PEREZ, R. O.; HABR-GAMA, A.; PEREIRA, G. V.; LYNN, P. B.; ALVES, P. A.; PROSCURSHIM, I.; RAWET, V.; GAMA-RODRIGUES, J.
    Aim The study aimed to determine the value of postchemoradiation biopsies, performed after significant tumour downsizing following neoadjuvant therapy, in predicting complete tumour regression in patients with distal rectal cancer. Method A retrospective comparative study was performed in patients with rectal cancer who achieved an incomplete clinical response after neoadjuvant chemoradiotherapy. Patients with significant tumour downsizing (> 30% of the initial tumour size) were compared with controls (< 30% reduction of the initial tumour size). During flexible proctoscopy carried out postchemoradiation, biopsies were performed using 3-mm biopsy forceps. The biopsy results were compared with the histopathological findings of the resected specimen. UICC (Union for International Cancer Control) ypTNM classification, tumour differentiation and regression grade were evaluated. The main outcome measures were sensitivity and specificity, negative and positive predictive values, and accuracy of a simple forceps biopsy for predicting pathological response after neoadjuvant chemoradiotherapy. Results Of the 172 patients, 112 were considered to have had an incomplete clinical response and were included in the study. Thirty-nine patients achieved significant tumour downsizing and underwent postchemoradiation biopsies. Overall, 53 biopsies were carried out. Of the 39 patients who achieved significant tumour downsizing, the biopsy result was positive in 25 and negative in 14. Only three of the patients with a negative biopsy result were found to have had a complete pathological response (giving a negative predictive value of 21%). Considering all biopsies performed, only three of 28 negative biopsies were true negatives, giving a negative predictive value of 11%. Conclusion In patients with distal rectal cancer undergoing neoadjuvant chemoradiation, post-treatment biopsies are of limited clinical value in ruling out persisting cancer. A negative biopsy result after a near-complete clinical response should not be considered sufficient for avoiding a radical resection.
  • article 34 Citação(ões) na Scopus
    Lateral Node Dissection in Rectal Cancer in the Era of Minimally Invasive Surgery: A Step-by-Step Description for the Surgeon Unacquainted with This Complex Procedure with the Use of the Laparoscopic Approach
    (2018) PEREZ, Rodrigo Oliva; JULIAO, Guilherme P. Sao; VAILATI, Bruna Borba; FERNANDEZ, Laura M.; MATTACHEO, Adrian E.; KONISHI, Tsuyoshi
    INTRODUCTION: Lateral node dissection in rectal cancer has been routinely performed in Eastern countries. Technical and anatomical challenges and potential significant postoperative morbidity associated with the procedure have prevented its implementation into clinical practice in Western countries. However, the minimally invasive approach may offer the opportunity of performing this complex procedure with precise anatomical dissection and minimal intraoperative blood loss. In this setting, proper training and standardization of technical steps is highly warranted for surgeons not fully acquainted with the procedure. TECHNIQUE: Access to the lateral nodes along the obturator and internal iliac vessels is described by using specific anatomical landmarks. Opening of the peritoneum along the ureter provides access to the region of interest. Dissection of the medial limit is performed preserving the neurovascular bundle and ureter. The lateral dissection is performed along the external iliac vein to provide access to the obturator muscle. Identification of the obturator nerve with blunt dissection of the fat is a critical part of the procedure. Once the lymphatic connections between the inguinal and iliac nodes are transected, dissection is performed along the internal iliac vessels, and branches are separated from the lymphadenectomy specimen. RESULTS: Evidence supports that lateral node dissection performed for highly selected patients with minimally invasive access leads to less intraoperative blood loss and similar oncological outcomes. Technical steps illustrated in the present video may aid surgeons in performing this procedure with precise anatomical landmarks and minimal risk for intraoperative complications. CONCLUSIONS: Lateral node dissection for rectal cancer is a procedure that may follow standardized technical steps by using precise anatomical landmarks with the use of minimally invasive approach.
  • article 11 Citação(ões) na Scopus
    Magnetic resonance imaging following neoadjuvant chemoradiation and transanal endoscopic microsurgery for rectal cancer
    (2017) JULIAO, G. P. Sao; ORTEGA, C. D.; VAILATI, B. B.; HABR-GAMA, A.; FERNANDEZ, L. M.; GAMA-RODRIGUES, J.; ARAUJO, S. E.; PEREZ, R. O.
    Aim Full-thickness local excision after neoadjuvant chemoradiotherapy (CRT) for patients with rectal cancer and incomplete clinical response has been a treatment strategy for organ preservation. Follow-up of these patients is challenging since anatomic distortion and postoperative changes may be clinically indistinguishable from tumour recurrence. MRI may have a role in detecting recurrence. The aim of this study was to describe the MRI findings during follow-up in patients having local excision following CRT with and without local recurrence. Method The data were collected retrospectively from a single centre. Fifty-three patients with rectal cancer who had full-thickness local excision after neoadjuvant CRT and near-complete response were eligible for the study. Patients with local recurrence were treated by radical salvage surgery. The main outcome was local MRI assessment findings during follow-up. Results Fifteen patients (five who developed local recurrence and 10 with no evidence of local recurrence) had MR images available for review and were included in the study. High signal intensity and thickening of the rectal wall were present in all patients with recurrent disease within the rectal wall. Overall, 80% of the patients with recurrence showed diffusion restriction. MRI mesorectal fascia status and circumferential resection margin showed agreement in all cases. A low signal intensity scar was seen in all patients without recurrent disease. Conclusion MRI shows high signal intensity and thickening of the rectal wall in recurrent disease in comparison to a low signal intensity fibrotic scar in non-recurrent disease. These findings may be useful in surveillance of these patients.